1. Field of the Invention
This invention relates to the control of nematodes and other helminths and more specifically to the control of these parasites with certain esters of alkanephosphonic acids.
2. Description of the Art
Phosphorous containing organic compounds are known to be useful as wetting agents and detergents, plasticizers for many plastics and resins, bonding agents for asphalt and similar compositions, lubricants, lubricant additives, corrosion inhibitors, flame proofing agents and as general agricultural household chemicals including insecticides and pesticides. They are also known to be useful as fire retardants and textile treating agents and have also been disclosed as antimicrobial agents.
A particular shortcoming in the control of nematodes is the small number of nematicides, approximately 25, that are now registered with the Environmental Protection Agency and available for use. This number, when compared to the approximately 125 herbicides and 230 insecticides registered for use, indicates the relatively primitive state of the art of nematode control. Furthermore of the 25 registered nematicides, many are restricted to specific uses and cannot be used for general treatment purposes. In addition, some are hazardous to vertebrates. Eight are organophosphates and carbamates which are hazardous not only to vertebrates but also to the surrounding environment. Nematode control capabilities are being reduced even further by severe restrictions or by cancellations, either actual or threatened, by the Environmental Protection Agency of several of the most widely used halogenated hydrocarbon fumigants.